Ma Navu is based on Isaiah 52:7:

How beautiful on the mountains are
the feet of him who brings good news,
who announces shalom,
who brings good news of happiness,
who announces salvation,
who says to Zion, “Your God reigns!”

מַה־נָּאו֨וּ עַל־הֶהָרִ֜ים רַגְלֵ֣י מְבַשֵּׂ֗ר מַשְׁמִ֧יעַ שָׁל֛וֹם מְבַשֵּׂ֥ר ט֖וֹב מַשְׁמִ֣יעַ יְשׁוּעָ֑ה אֹמֵ֥ר לְצִיּ֖וֹן מָלַ֥ךְ אֱלֹהָֽיִךְ